Orthopedic jig, pin, and method

ABSTRACT

An orthopedic jig and pins therefore are disclosed that allow the pins to be pre-loaded into apertures through the jig before the jig is positioned at a desired location with respect to a bone during an orthopedic surgical procedure. At least one of the pin and/or jig includes a retention mechanism whereby the pin can be inserted into the bore and releasably restrained therein until the jig is place in the selected position and the pins driven into the bone.

CROSS REFERENCE TO RELATED APPLICATIONS

Not applicable

REFERENCE REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable

SEQUENTIAL LISTING

Not applicable

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to surgical instruments.

2. Description of the Background of the Invention

In orthopedic surgery, pins are regularly used to temporarily affixjigs, such as cutting blocks, to the bone. A standard technique foraffixing a jig to a bone is for a surgeon to hold the jig to the bone,carefully insert the pins through apertures in the jig, and then drivethe pins into the bone through the holes in order to achieve thefixation. The number of pins needed for affixing each jig variestypically between two and four, and often two or more jigs need to betemporarily affixed to the bone. Consequently, sometimes ten or morepins need to be inserted to the jigs and drilled into the bone during asurgical procedure. This pin insertion process must be done verycarefully by the surgeon in order to carefully avoid pin jamming orstripping and can take up so several seconds or longer for each pin. Asa result, the total time for pinning can add several minutes or more toa surgical procedure requiring a larger number of jigs.

SUMMARY OF THE INVENTION

According to one aspect of the invention, a pin for use with anorthopedic jig includes a shaft adapted to slide through an apertureassociated with the jig and a restraining member disposed on the shaft.The restraining member is adapted to releasably hold the pin within theaperture.

According to another aspect of the invention, an orthopedic jig incombination with a pin includes a jig body defining an aperturetherethrough, a pin disposed through the aperture, and a restrainingmember associated with at least one of the jig body and the pin. Therestraining member releasably restrains the pin within the apertureprior to fixation to a support surface.

According to yet another aspect of the invention, a jig adapted forfixation to a bone with a pin during an orthopedic surgical procedureincludes a body, an aperture associated with the body and adapted toreceive the pin therethrough, and a retention mechanism adapted toreleasably restrain the pin in the aperture.

According to a further aspect of the invention, a method of attaching ajig to a bone during a surgery includes the steps of releasably securinga pin within a bore defined by a jig using a retention mechanismassociated with one of the jig and the pin at a location removed fromthe bone, engaging the jig with the bone, and driving the pin into thebone.

Other aspects and advantages of the present invention will becomeapparent upon consideration of the following detailed and descriptiondrawings in which like numbers are used to designate similar structuresin various embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary schematic isometric view of an orthopedic jigpinned to a bone according to one aspect of the present invention;

FIG. 2 is a fragmentary isometric view of a pin according to anotheraspect of the present invention;

FIG. 3 is a fragmentary cross-sectional view of a the pin of FIG. 2pre-loaded into an aperture through a jig;

FIG. 4 is a fragmentary isometric view of a pin according to anotheraspect of the present invention;

FIG. 5 is a fragmentary cross-sectional view of the pin of FIG. 4pre-loaded into an aperture through a jig;

FIG. 6 is a fragmentary cross-sectional view of a jig and pin accordingto a further aspect of the present invention;

FIG. 7 is a fragmentary cross-sectional view of a jig and pin accordingto yet another aspect of the present invention; and

FIG. 8 is a fragmentary side view of a jig and pin according to a stillfurther embodiment of the present invention with portions shown cutawayand in cross-section for clarity.

DETAILED DESCRIPTION

With reference to FIG. 1, a jig 10 for use in orthopedic surgicalprocedures includes apertures, such as through bores 12, for receivingpins 14 therethrough for attaching the jig to a work surface, such as abone 16 during the surgical procedure. The pins 14 are releasablysecured in the bores 12, such as by adhesive, clamping, and/or lockingaction, prior to attachment to the bone 16 by a restraining memberassociated with at least one of the jig 10 and the pin so that the pinsmay be pre-loaded within the bores in an area away from the surgicalprocedure by one person and subsequently engaged with the bone with thepre-loaded pins already releasably held within the bores by anotherperson at the surgical procedure. Preferably, the restraining member isdisposed and adapted so that an end of the pin 14 that is to be insertedinto the bone is releasably retained within the bore 12, although inother embodiments the restraining member may be adapted to releasablyretain the pin in other selected orientations in the aperture.Thereafter, a shaft 18 of each pin 14 may be driven through the bore 12into the bone 16 by any appropriate method, such as drilling, screwing,or hammering, for example, to secure the jig 10 in a selectedorientation with respect to the bone.

FIGS. 2 and 3 show one embodiment in which the restraining member isassociated with a pin 14. In this embodiment, the restraining membercomprises a film of adhesive 20 disposed around a peripheral surface ofthe shaft 18 of the pin 14, as best shown in FIG. 2. When the shaft 18is inserted into the bore 12, the adhesive 20 adheres lightly to theinner surface of the bore 12, which is smooth in this embodiment,whereby the pin is releasably retained in the bore until the pin isdriven into the bone 16 by any normal method. The adhesive 20 ispreferably disposed near an end 22 of the shaft 18 that is adapted forbeing driven into the bone 16, such as by an insertion tip, so that theend 22 will reside within the aperture 12, as shown in FIG. 3. Theadhesive 20 may be applied immediately before the pin 14 is to be used,or the pin may be pre-formed to include a film of adhesive and include,for example, a removable cover strip (not shown) to protect the adhesivefrom unwanted debris during storage. The pin 14, in one embodiment, mayinclude threads 24 along the shaft 18 to facilitate screwing into thebone 16. In other embodiments, the shaft may be smooth, have otherrelief, such as grooves or ridges (not shown), or include other featuresdesired for a particular use.

Turning now to the embodiment shown in FIGS. 4 and 5, the pin 14 carriesa resilient member, such as a tension ring 30, that frictionally engagesthe inner surface of the bore 12 to releasably restrain the pin in thebore. The tension ring 30 is disposed in an outer peripheral groove 32that circumscribes the shaft 18 near the end 22. When the tension ring30 is in a relaxed state, the outer diameter extends radially beyond thesurface of the shaft 18 and has a larger diameter than a minimumdiameter of the bore 12, and the inner diameter is disposed inside theouter peripheral groove 32 so that tension ring does not fall off theshaft. A radial gap 34 allows the tension ring 30 to resilientlycontract and expand. The outer peripheral groove 32 has a depthsufficient to allow the tension ring 30 to be constricted so as to bereceived within the bore 12. In one embodiment, the outer peripheralgroove 32 has a depth sufficient to allow the tension ring 30 to becompletely disposed therein such that the outside diameter of thetension ring is substantially coextensive with the diameter of the shaft18 adjacent the outer peripheral groove. Thereby, the shaft 18 and thetension ring 30 may be inserted into a bore 12 having an inside diametersubstantially equal to the diameter of the shaft, and the tension ringresiliently urges outward against the interior surface of the bore witha force F_(s) to releasably retain the end 22 of the pin in the bore byclamping action until the pin is driven into the bone 16. In oneembodiment, the tension ring 30 includes a tapered leading edge 36,which may facilitate driving the end 22 and the tension ring 30 directlyinto the bone 16 and also facilitate retaining the pin in the bonethereafter.

FIG. 6 shows an embodiment in which the restraining member is associatedwith the jig 10. In this embodiment, a tension ring 30 is disposed in aninner peripheral groove 40 that is defined completely around the innersurface of the bore 12. In a relaxed state, the outside diameter of thetension ring 30 is larger than the inside diameter of the bore 12, andthe inside diameter of the tension ring is smaller than the outsidediameter of the shaft 18 of the pin 14. The inner peripheral groove 40has a depth sufficient to allow the tension ring 30 to expand enough toreceive the shaft 18 of the pin 14 therethrough, and in one embodiment,the inner peripheral groove is at least as deep as a thickness of thetension ring. Thereby, the tension ring 30 is normally carried by thejig 10, and when the pin 14 is inserted into the bore 12, the tensionring resiliently expands around the shaft 18 and frictionally grips theshaft with a spring force F_(s) to releasably retain the end 22 of thepin in the bore by clamping action. In one embodiment, the shaft 18 mayalso include an outer peripheral groove 32 having at least a taperedtrailing edge 42 adapted to receive the tension ring 30, therebyallowing the tension ring to releasably lockingly engage the pin at theouter peripheral groove in addition or alternative to clamping.

FIG. 7 shows another embodiment in which the restraining member isassociated with the jig 10. In this embodiment, a ball plunger 50carried by the jig 10 is disposed in the bore 12 to releasably restrainthe shaft 18 of the pin 14 therein by clamping and/or locking. In oneembodiment, the ball plunger 50 includes one or more ball members 52that are resiliently urged, such as with a tension ring 30, into thebore 12 from one or more recesses, such as an inner peripheral groove40, in the inner surface of the bore. In a relaxed state, the ballmembers 52 protrude into the bore 12. When the pin 14 is inserted intothe bore, the ball members 52 press resiliently against the shaft toreleasably restrain the end 22 of the shaft in the bore by clamping. Inone embodiment, the shaft 18 may be smooth, and in another embodiment,the shaft 18 also may include a recess, such as a shallow outerperipheral groove 32, located and adapted to receive a portion of theball members 52 therein and provide an additional resilient lockingmechanism for releasably retaining the pin 14 in the bore 12 in additionor alternative to clamping.

In FIG. 8, another embodiment is shown in which the pin 14 includesresilient retention mechanism, such as a ball plunger 50, to resilientlyengage the bore 12 through the jig 10 in order to retain the pin in adesired preloaded position within the bore. The ball plunger 50 includesa ball member 52 disposed in a blind bore 60 that extends generallytransversely to a longitudinal axis of the pin. The blind bore 60 has anopening through an exterior surface of the pin through which a portionof the ball member 52 extends to engage the bore 12 of the jig. Anarrowed neck 62 portion of the bore retains the ball member 52 insidethe blind bore 60, and a resilient member, such as a spring 64, urgesthe ball member radially outwardly. Preferably, the ball plunger 50 islocated near the tip 22 of the pin 14 so that the tip of the pin isretained within the bore 12 of the jig 10, but in other embodiments, theball plunger may be located anywhere along the length of pin. When thetip 22 of the pin 14 is inserted into the bore 12 of the jig 10, thespring 64 presses the ball member 52 resiliently against the bore 12,which retains the pin inside the bore 12. The bore 12 of the jig 10 maybe smooth or the bore 12, in which case the ball plunger 50 simplyclamps the pin inside the bore 12, or the bore may include a receivingrecess for the ball plunger 50, such as an inner peripheral groove 66,to releasably lockingly engage the pin 14 in a pre-loaded positionwithin the bore 12 in addition or alternative to clamping. In theembodiment shown in FIG. 8, the pin 14 has a single locked pre-loadedposition. Other embodiments may include additional ball plungers 50located at other locations along the length of the pin 14 and/oradditional grooves 66 along the length of the bore 12 to providemultiple locked and/or clamped pre-loaded positions.

The jig 10 and pins 14 disclosed herein allow a method of attaching thejig to a bone during a surgery. In one possible method of affixing anyone of the jigs 10 disclosed herein to a bone 16, a scrub nurse maypre-load the appropriate pins 14 to the appropriate jig 10, i.e., insertthe insertion end 22 of the pin into the bore 12, before the surgicalprocedure or otherwise away from the immediate temporal or physicalvicinity of the incision or wound through which the jig will be affixedto the bone 16. Subsequently, the pre-loaded jig 10 with the pins 14releasably restrained in the bores 12 may be given to the surgeon, forexample, at the time when required for fixation to the bone 16. Thesurgeon may then position the jig 10 with the pre-loaded pins 14 at aselected position with respect to the bone 16 through the incision orwound and then drive the pins 14 through the bore 12 into the bone in anappropriate manner. If a surgical navigational system (not shown) isbeing used during the procedure, the jig 10 and/or pins 14 may beadapted for integration and use therewith during the affixationprocedure.

INDUSTRIAL APPLICABILITY

The present invention may be useful at least in orthopedic surgicalprocedures. By allowing the pins 14 to be pre-loaded to a jig 10 by thesurgeon or by someone other than the surgeon during an orthopedicsurgical procedure, the devices and methods disclosed herein may, insome circumstances, reduce the time needed by the surgeon during asurgical procedure to affix a jig to a patient, thereby possiblyreducing the overall time and cost of the surgical procedure over priorjigs and methods of attachment. Other industrial applications are alsopossible.

Numerous modifications to the present invention will be apparent tothose skilled in the art in view of the foregoing description. Inaddition, all possible combinations and sub-combinations of theembodiments disclosed herein are specifically contemplated and expresslyincluded in the scope of the present disclosure. Accordingly, thisdescription is to be construed as illustrative only and is presented forthe purpose of enabling those skilled in the art to make and use theinvention and to teach the best mode of carrying out same. The exclusiverights to all modifications that come within the scope of the impendingclaims are hereby reserved.

1. A pin for use with an orthopedic jig, the pin comprising: a shaftadapted to slide through an aperture associated with the jig; and arestraining member disposed on the shaft, wherein the restraining memberis adapted to releasably hold the pin within the aperture.
 2. The pin ofclaim 1, wherein the restraining member is disposed proximate aninsertion tip end of the pin.
 3. The pin of claim 1, wherein therestraining member comprises a resilient member that is adapted to clampthe pin inside the bore.
 4. The pin of claim 3, wherein the restrainingmember comprises a tension ring adapted to fit through the aperture andresiliently engage an interior surface of the aperture.
 5. The pin ofclaim 4, further comprising a peripheral groove in the shaft, whereinthe tension ring is disposed in the groove.
 6. The pin of claim 5,wherein the tension ring has a peripheral surface disposed radiallybeyond an adjacent surface of the shaft in a relaxed state.
 7. The pinof claim 6, wherein the tension ring has an outside diameter larger thanan adjacent portion of the shaft and larger than an inside diameter ofthe aperture in a relaxed state.
 8. The pin of claim 3, wherein therestraining member comprises a ball plunger.
 9. The pin of claim 1,wherein the restraining member comprises an adhesive located so as toengage an interior surface of the aperture.
 10. The pin of claim 9,wherein the adhesive comprises a film of adhesive disposed around thepin.
 11. The pin of claim 1, further comprising threads adapted forscrewing the shaft into a bone.
 12. An orthopedic jig in combinationwith a pin, the combination comprising: a pin disposed through a boredefined by the jig; and a restraining member associated with at leastone of the jig and the pin, wherein the restraining member releasablyrestrains the pin within the bore prior to fixation of the pin to asupport surface.
 13. The combination of claim 12, wherein therestraining member comprises an adhesive disposed on the pin.
 14. Thecombination of claim 12, wherein the restraining member comprises aclamping member associated with the jig that restrains the pin.
 15. Thecombination of claim 14, wherein the pin further comprises a recess thatreleasably locks with the clamping member.
 16. The combination of claim14, wherein the clamping member comprises a tension ring carried by thejig.
 17. The combination of claim 14, wherein the clamping membercomprises a ball plunger carried by the jig.
 18. The combination ofclaim 12, wherein the restraining member comprises a clamping memberassociated with the pin that resiliently engages an inner surface of thebore.
 19. The combination of claim 18, wherein the restraining membercomprises a plurality of clamping members associated with the pin, eachclamping member adapted to resiliently engage the inner surface of thebore.
 20. The combination of claim 18, further comprising a recess inthe inner surface of the bore that releasably locks with the clampingmember.
 21. The combination of claim 18, wherein the clamping membercomprises a tension ring carried by the pin.
 22. The combination ofclaim 21 further comprising a groove in the pin, wherein the groove isadapted to completely receive the tension ring therein.
 23. Thecombination of claim 22, wherein the tension ring has a peripheral edgethat is disposed beyond a radial periphery of the pin in a relaxedstate.
 24. The combination of claim 18, wherein the clamping membercomprises a ball plunger carried by the pin.
 25. A jig adapted forfixation to a bone with a pin during an orthopedic surgical procedure,the jig comprising: a body; an aperture associated with the body andadapted to receive the pin therethrough; and a retention mechanismadapted to releasably restrain the pin in the aperture.
 26. The jig ofclaim 25, wherein the retention mechanism comprises a resilient memberadapted to engage the pin when disposed in the aperture.
 27. The jig ofclaim 25, wherein the retention mechanism comprises a ball plungeradapted to resiliently engage the pin when disposed in the aperture 28.The jig of claim 25, wherein the retention mechanism comprises a tensionring adapted to resiliently engage the pin when disposed in theaperture.
 29. A method of attaching a jig to a bone during a surgery,the method comprising the steps of: releasably securing a pin within abore defined by a jig using a retention mechanism associated with one ofthe jig and the pin at a location removed from the bone; engaging thejig with the bone; driving the pin through the bore into the bone. 30.The method of claim 29, further comprising the step of using the pin inconjunction with a surgical navigation system.
 31. The method of claim29, wherein the retention mechanism comprises an adhesive carried by thepin disposed proximate a tip end of the pin.
 32. The method of claim 29,wherein the step of securing further comprises the step of releasablylocking the pin in the bore.
 33. The method of claim 29, wherein thestep of securing comprises the step of engaging the pin with a clampingmechanism associated with the jig to releasably retain the pin in thebore.
 34. The method of claim 33, wherein the clamping mechanismcomprises a ball plunger.
 35. The method of claim 34, wherein theclamping mechanism comprises a tension ring.
 36. The method of claim 29,wherein the step of securing further comprises the step of engaging thebore with a clamping mechanism associated with the pin adapted toreleasably retain the pin in the bore.
 37. The method of claim 36,wherein the clamping mechanism comprises a resilient member that engagesthe bore.
 38. The method of claim 37, wherein the resilient membercomprises a tension ring.
 39. The method of claim 37, wherein theresilient member comprises a ball plunger.
 40. The method of claim 29,wherein the step of securing is performed by a first person, and whereinthe steps of engaging and driving are performed by at least a secondperson.